1 The quantities listed above were derived by taking 1/10th of the most restrictive ALI listed in table 1, columns 1 and 2, of appendix B to §§ 20.1001-20.2401 of this part, rounding to the nearest factor of 10, and arbitrarily constraining the values listed between 0.001 and 1,000 µCi. Values of 100 µCi have been assigned for radionuclides having a radioactive half-life in excess of 109 years (except rhenium, 1000 µCi) to take into account their low specific activity.

Note: For purposes of §§ 20.1902(e), 20.1905(a), and 20.2201(a) where there is involved a combination of radionuclides in known amounts, the limit for the combination should be derived as follows: determine, for each radionuclide in the combination, the ratio between the quantity present in the combination and the limit otherwise established for the specific radionuclide when not in combination. The sum of such ratios for all radionuclides in the combination may not exceed “1” (i.e., “unity”).

Hydrogen-3

1,000

Beryllium-7

1,000

Beryllium-10

1

Carbon-11

1,000

Carbon-14

100

Fluorine-18

1,000

Sodium-22

10

Sodium-24

100

Magnesium-28

100

Aluminum-26

10

Silicon-31

1,000

Silicon-32

1

Phosphorus-32

10

Phosphorus-33

100

Sulfur-35

100

Chlorine-36

10

Chlorine-38

1,000

Chlorine-39

1,000

Argon-39

1,000

Argon-41

1,000

Potassium-40

100

Potassium-42

1,000

Potassium-43

1,000

Potassium-44

1,000

Potassium-45

1,000

Calcium-41

100

Calcium-45

100

Calcium-47

100

Scandium-43

1,000

Scandium-44m

100

Scandium-44

100

Scandium-46

10

Scandium-47

100

Scandium-48

100

Scandium-49

1,000

Titanium-44

1

Titanium-45

1,000

Vanadium-47

1,000

Vanadium-48

100

Vanadium-49

1,000

Chromium-48

1,000

Chromium-49

1,000

Chromium-51

1,000

Manganese-51

1,000

Manganese-52m

1,000

Manganese-52

100

Manganese-53

1,000

Manganese-54

100

Manganese-56

1,000

Iron-52

100

Iron-55

100

Iron-59

10

Iron-60

1

Cobalt-55

100

Cobalt-56

10

Cobalt-57

100

Cobalt-58m

1,000

Cobalt-58

100

Cobalt-60m

1,000

Cobalt-60

1

Cobalt-61

1,000

Cobalt-62m

1,000

Nickel-56

100

Nickel-57

100

Nickel-59

100

Nickel-63

100

Nickel-65

1,000

Nickel-66

10

Copper-60

1,000

Copper-61

1,000

Copper-64

1,000

Copper-67

1,000

Zinc-62

100

Zinc-63

1,000

Zinc-65

10

Zinc-69m

100

Zinc-69

1,000

Zinc-71m

1,000

Zinc-72

100

Gallium-65

1,000

Gallium-66

100

Gallium-67

1,000

Gallium-68

1,000

Gallium-70

1,000

Gallium-72

100

Gallium-73

1,000

Germanium-66

1,000

Germanium-67

1,000

Germanium-68

10

Germanium-69

1,000

Germanium-71

1,000

Germanium-75

1,000

Germanium-77

1,000

Germanium-78

1,000

Arsenic-69

1,000

Arsenic-70

1,000

Arsenic-71

100

Arsenic-72

100

Arsenic-73

100

Arsenic-74

100

Arsenic-76

100

Arsenic-77

100

Arsenic-78

1,000

Selenium-70

1,000

Selenium-73m

1,000

Selenium-73

100

Selenium-75

100

Selenium-79

100

Selenium-81m

1,000

Selenium-81

1,000

Selenium-83

1,000

Bromine-74m

1,000

Bromine-74

1,000

Bromine-75

1,000

Bromine-76

100

Bromine-77

1,000

Bromine-80m

1,000

Bromine-80

1,000

Bromine-82

100

Bromine-83

1,000

Bromine-84

1,000

Krypton-74

1,000

Krypton-76

1,000

Krypton-77

1,000

Krypton-79

1,000

Krypton-81

1,000

Krypton-83m

1,000

Krypton-85m

1,000

Krypton-85

1,000

Krypton-87

1,000

Krypton-88

1,000

Rubidium-79

1,000

Rubidium-81m

1,000

Rubidium-81

1,000

Rubidium-82m

1,000

Rubidium-83

100

Rubidium-84

100

Rubidium-86

100

Rubidium-87

100

Rubidium-88

1,000

Rubidium-89

1,000

Strontium-80

100

Strontium-81

1,000

Strontium-83

100

Strontium-85m

1,000

Strontium-85

100

Strontium-87m

1,000

Strontium-89

10

Strontium-90

0.1

Strontium-91

100

Strontium-92

100

Yttrium-86m

1,000

Yttrium-86

100

Yttrium-87

100

Yttrium-88

10

Yttrium-90m

1,000

Yttrium-90

10

Yttrium-91m

1,000

Yttrium-91

10

Yttrium-92

100

Yttrium-93

100

Yttrium-94

1,000

Yttrium-95

1,000

Zirconium-86

100

Zirconium-88

10

Zirconium-89

100

Zirconium-93

1

Zirconium-95

10

Zirconium-97

100

Niobium-88

1,000

Niobium-89m (66 min)

1,000

Niobium-89 (122 min)

1,000

Niobium-90

100

Niobium-93m

10

Niobium-94

1

Niobium-95m

100

Niobium-95

100

Niobium-96

100

Niobium-97

1,000

Niobium-98

1,000

Molybdenum-90

100

Molybdenum-93m

100

Molybdenum-93

10

Molybdenum-99

100

Molybdenum-101

1,000

Technetium-93m

1,000

Technetium-93

1,000

Technetium-94m

1,000

Technetium-94

1,000

Technetium-96m

1,000

Technetium-96

100

Technetium-97m

100

Technetium-97

1,000

Technetium-98

10

Technetium-99m

1,000

Technetium-99

100

Technetium-101

1,000

Technetium-104

1,000

Ruthenium-94

1,000

Ruthenium-97

1,000

Ruthenium-103

100

Ruthenium-105

1,000

Ruthenium-106

1

Rhodium-99m

1,000

Rhodium-99

100

Rhodium-100

100

Rhodium-101m

1,000

Rhodium-101

10

Rhodium-102m

10

Rhodium-102

10

Rhodium-103m

1,000

Rhodium-105

100

Rhodium-106m

1,000

Rhodium-107

1,000

Palladium-100

100

Palladium-101

1,000

Palladium-103

100

Palladium-107

10

Palladium-109

100

Silver-102

1,000

Silver-103

1,000

Silver-104m

1,000

Silver-104

1,000

Silver-105

100

Silver-106m

100

Silver-106

1,000

Silver-108m

1

Silver-110m

10

Silver-111

100

Silver-112

100

Silver-115

1,000

Cadmium-104

1,000

Cadmium-107

1,000

Cadmium-109

1

Cadmium-113m

0.1

Cadmium-113

100

Cadmium-115m

10

Cadmium-115

100

Cadmium-117m

1,000

Cadmium-117

1,000

Indium-109

1,000

Indium-110 (69.1min.)

1,000

Indium-110

(4.9h)

1,000

Indium-111

100

Indium-112

1,000

Indium-113m

1,000

Indium-114m

10

Indium-115m

1,000

Indium-115

100

Indium-116m

1,000

Indium-117m

1,000

Indium-117

1,000

Indium-119m

1,000

Tin-110

100

Tin-111

1,000

Tin-113

100

Tin-117m

100

Tin-119m

100

Tin-121m

100

Tin-121

1,000

Tin-123m

1,000

Tin-123

10

Tin-125

10

Tin-126

10

Tin-127

1,000

Tin-128

1,000

Antimony-115

1,000

Antimony-116m

1,000

Antimony-116

1,000

Antimony-117

1,000

Antimony-118m

1,000

Antimony-119

1,000

Antimony-120 (16min.)

1,000

Antimony-120 (5.76d)

100

Antimony-122

100

Antimony-124m

1,000

Antimony-124

10

Antimony-125

100

Antimony-126m

1,000

Antimony-126

100

Antimony-127

100

Antimony-128 (10.4min.)

1,000

Antimony-128 (9.01h)

100

Antimony-129

100

Antimony-130

1,000

Antimony-131

1,000

Tellurium-116

1,000

Tellurium-121m

10

Tellurium-121

100

Tellurium-123m

10

Tellurium-123

100

Tellurium-125m

10

Tellurium-127m

10

Tellurium-127

1,000

Tellurium-129m

10

Tellurium-129

1,000

Tellurium-131m

10

Tellurium-131

100

Tellurium-132

10

Tellurium-133m

100

Tellurium-133

1,000

Tellurium-134

1,000

Iodine-120m

1,000

Iodine-120

100

Iodine-121

1,000

Iodine-123

100

Iodine-124

10

Iodine-125

1

Iodine-126

1

Iodine-128

1,000

Iodine-129

1

Iodine-130

10

Iodine-131

1

Iodine-132m

100

Iodine-132

100

Iodine-133

10

Iodine-134

1,000

Iodine-135

100

Xenon-120

1,000

Xenon-121

1,000

Xenon-122

1,000

Xenon-123

1,000

Xenon-125

1,000

Xenon-127

1,000

Xenon-129m

1,000

Xenon-131m

1,000

Xenon-133m

1,000

Xenon-133

1,000

Xenon-135m

1,000

Xenon-135

1,000

Xenon-138

1,000

Cesium-125

1,000

Cesium-127

1,000

Cesium-129

1,000

Cesium-130

1,000

Cesium-131

1,000

Cesium-132

100

Cesium-134m

1,000

Cesium-134

10

Cesium-135m

1,000

Cesium-135

100

Cesium-136

10

Cesium-137

10

Cesium-138

1,000

Barium-126

1,000

Barium-128

100

Barium-131m

1,000

Barium-131

100

Barium-133m

100

Barium-133

100

Barium-135m

100

Barium-139

1,000

Barium-140

100

Barium-141

1,000

Barium-142

1,000

Lanthanum-131

1,000

Lanthanum-132

100

Lanthanum-135

1,000

Lanthanum-137

10

Lanthanum-138

100

Lanthanum-140

100

Lanthanum-141

100

Lanthanum-142

1,000

Lanthanum-143

1,000

Cerium-134

100

Cerium-135

100

Cerium-137m

100

Cerium-137

1,000

Cerium-139

100

Cerium-141

100

Cerium-143

100

Cerium-144

1

Praseodymium-136

1,000

Praseodymium-137

1,000

Praseodymium-138m

1,000

Praseodymium-139

1,000

Praseodymium-142m

1,000

Praseodymium-142

100

Praseodymium-143

100

Praseodymium-144

1,000

Praseodymium-145

100

Praseodymium-147

1,000

Neodymium-136

1,000

Neodymium-138

100

Neodymium-139m

1,000

Neodymium-139

1,000

Neodymium-141

1,000

Neodymium-147

100

Neodymium-149

1,000

Neodymium-151

1,000

Promethium-141

1,000

Promethium-143

100

Promethium-144

10

Promethium-145

10

Promethium-146

1

Promethium-147

10

Promethium-148m

10

Promethium-148

10

Promethium-149

100

Promethium-150

1,000

Promethium-151

100

Samarium-141m

1,000

Samarium-141

1,000

Samarium-142

1,000

Samarium-145

100

Samarium-146

1

Samarium-147

100

Samarium-151

10

Samarium-153

100

Samarium-155

1,000

Samarium-156

1,000

Europium-145

100

Europium-146

100

Europium-147

100

Europium-148

10

Europium-149

100

Europium-150 (12.62h)

100

Europium-150 (34.2y)

1

Europium-152m

100

Europium-152

1

Europium-154

1

Europium-155

10

Europium-156

100

Europium-157

100

Europium-158

1,000

Gadolinium-145

1,000

Gadolinium-146

10

Gadolinium-147

100

Gadolinium-148

0.001

Gadolinium-149

100

Gadolinium-151

10

Gadolinium-152

100

Gadolinium-153

10

Gadolinium-159

100

Terbium-147

1,000

Terbium-149

100

Terbium-150

1,000

Terbium-151

100

Terbium-153

1,000

Terbium-154

100

Terbium-155

1,000

Terbium-156m (5.0h)

1,000

Terbium-156m (24.4h)

1,000

Terbium-156

100

Terbium-157

10

Terbium-158

1

Terbium-160

10

Terbium-161

100

Dysprosium-155

1,000

Dysprosium-157

1,000

Dysprosium-159

100

Dysprosium-165

1,000

Dysprosium-166

100

Holmium-155

1,000

Holmium-157

1,000

Holmium-159

1,000

Holmium-161

1,000

Holmium-162m

1,000

Holmium-162

1,000

Holmium-164m

1,000

Holmium-164

1,000

Holmium-166m

1

Holmium-166

100

Holmium-167

1,000

Erbium-161

1,000

Erbium-165

1,000

Erbium-169

100

Erbium-171

100

Erbium-172

100

Thulium-162

1,000

Thulium-166

100

Thulium-167

100

Thulium-170

10

Thulium-171

10

Thulium-172

100

Thulium-173

100

Thulium-175

1,000

Ytterbium-162

1,000

Ytterbium-166

100

Ytterbium-167

1,000

Ytterbium-169

100

Ytterbium-175

100

Ytterbium-177

1,000

Ytterbium-178

1,000

Lutetium-169

100

Lutetium-170

100

Lutetium-171

100

Lutetium-172

100

Lutetium-173

10

Lutetium-174m

10

Lutetium-174

10

Lutetium-176m

1,000

Lutetium-176

100

Lutetium-177m

10

Lutetium-177

100

Lutetium-178m

1,000

Lutetium-178

1,000

Lutetium-179

1,000

Hafnium-170

100

Hafnium-172

1

Hafnium-173

1,000

Hafnium-175

100

Hafnium-177m

1,000

Hafnium-178m

0.1

Hafnium-179m

10

Hafnium-180m

1,000

Hafnium-181

10

Hafnium-182m

1,000

Hafnium-182

0.1

Hafnium-183

1,000

Hafnium-184

100

Tantalum-172

1,000

Tantalum-173

1,000

Tantalum-174

1,000

Tantalum-175

1,000

Tantalum-176

100

Tantalum-177

1,000

Tantalum-178

1,000

Tantalum-179

100

Tantalum-180m

1,000

Tantalum-180

100

Tantalum-182m

1,000

Tantalum-182

10

Tantalum-183

100

Tantalum-184

100

Tantalum-185

1,000

Tantalum-186

1,000

Tungsten-176

1,000

Tungsten-177

1,000

Tungsten-178

1,000

Tungsten-179

1,000

Tungsten-181

1,000

Tungsten-185

100

Tungsten-187

100

Tungsten-188

10

Rhenium-177

1,000

Rhenium-178

1,000

Rhenium-181

1,000

Rhenium-182 (12.7h)

1,000

Rhenium-182 (64.0h)

100

Rhenium-184m

10

Rhenium-184

100

Rhenium-186m

10

Rhenium-186

100

Rhenium-187

1,000

Rhenium-188m

1,000

Rhenium-188

100

Rhenium-189

100

Osmium-180

1,000

Osmium-181

1,000

Osmium-182

100

Osmium-185

100

Osmium-189m

1,000

Osmium-191m

1,000

Osmium-191

100

Osmium-193

100

Osmium-194

1

Iridium-182

1,000

Iridium-184

1,000

Iridium-185

1,000

Iridium-186

100

Iridium-187

1,000

Iridium-188

100

Iridium-189

100

Iridium-190m

1,000

Iridium-190

100

Iridium-192 (73.8d)

1

Iridium-192m (1.4min.)

10

Iridium-194m

10

Iridium-194

100

Iridium-195m

1,000

Iridium-195

1,000

Platinum-186

1,000

Platinum-188

100

Platinum-189

1,000

Platinum-191

100

Platinum-193m

100

Platinum-193

1,000

Platinum-195m

100

Platinum-197m

1,000

Platinum-197

100

Platinum-199

1,000

Platinum-200

100

Gold-193

1,000

Gold-194

100

Gold-195

10

Gold-198m

100

Gold-198

100

Gold-199

100

Gold-200m

100

Gold-200

1,000

Gold-201

1,000

Mercury-193m

100

Mercury-193

1,000

Mercury-194

1

Mercury-195m

100

Mercury-195

1,000

Mercury-197m

100

Mercury-197

1,000

Mercury-199m

1,000

Mercury-203

100

Thallium-194m

1,000

Thallium-194

1,000

Thallium-195

1,000

Thallium-197

1,000

Thallium-198m

1,000

Thallium-198

1,000

Thallium-199

1,000

Thallium-200

1,000

Thallium-201

1,000

Thallium-202

100

Thallium-204

100

Lead-195m

1,000

Lead-198

1,000

Lead-199

1,000

Lead-200

100

Lead-201

1,000

Lead-202m

1,000

Lead-202

10

Lead-203

1,000

Lead-205

100

Lead-209

1,000

Lead-210

0.01

Lead-211

100

Lead-212

1

Lead-214

100

Bismuth-200

1,000

Bismuth-201

1,000

Bismuth-202

1,000

Bismuth-203

100

Bismuth-205

100

Bismuth-206

100

Bismuth-207

10

Bismuth-210m

0.1

Bismuth-210

1

Bismuth-212

10

Bismuth-213

10

Bismuth-214

100

Polonium-203

1,000

Polonium-205

1,000

Polonium-207

1,000

Polonium-210

0.1

Astatine-207

100

Astatine-211

10

Radon-220

1

Radon-222

1

Francium-222

100

Francium-223

100

Radium-223

0.1

Radium-224

0.1

Radium-225

0.1

Radium-226

0.1

Radium-227

1,000

Radium-228

0.1

Actinium-224

1

Actinium-225

0.01

Actinium-226

0.1

Actinium-227

0.001

Actinium-228

1

Thorium-226

10

Thorium-227

0.01

Thorium-228

0.001

Thorium-229

0.001

Thorium-230

0.001

Thorium-231

100

Thorium-232

100

Thorium-234

10

Thorium-natural

100

Protactinium-227

10

Protactinium-228

1

Protactinium-230

0.1

Protactinium-231

0.001

Protactinium-232

1

Protactinium-233

100

Protactinium-234

100

Uranium-230

0.01

Uranium-231

100

Uranium-232

0.001

Uranium-233

0.001

Uranium-234

0.001

Uranium-235

0.001

Uranium-236

0.001

Uranium-237

100

Uranium-238

100

Uranium-239

1,000

Uranium-240

100

Uranium-natural

100

Neptunium-232

100

Neptunium-233

1,000

Neptunium-234

100

Neptunium-235

100

Neptunium-236 (1.15×105 y)

0.001

Neptunium-236 (22.5h)

1

Neptunium-237

0.001

Neptunium-238

10

Neptunium-239

100

Neptunium-240

1,000

Plutonium-234

10

Plutonium-235

1,000

Plutonium-236

0.001

Plutonium-237

100

Plutonium-238

0.001

Plutonium-239

0.001

Plutonium-240

0.001

Plutonium-241

0.01

Plutonium-242

0.001

Plutonium-243

1,000

Plutonium-244

0.001

Plutonium-245

100

Americium-237

1,000

Americium-238

100

Americium-239

1,000

Americium-240

100

Americium-241

0.001

Americium-242m

0.001

Americium-242

10

Americium-243

0.001

Americium-244m

100

Americium-244

10

Americium-245

1,000

Americium-246m

1,000

Americium-246

1,000

Curium-238

100

Curium-240

0.1

Curium-241

1

Curium-242

0.01

Curium-243

0.001

Curium-244

0.001

Curium-245

0.001

Curium-246

0.001

Curium-247

0.001

Curium-248

0.001

Curium-249

1,000

Berkelium-245

100

Berkelium-246

100

Berkelium-247

0.001

Berkelium-249

0.1

Berkelium-250

10

Californium-244

100

Californium-246

1

Californium-248

0.01

Californium-249

0.001

Californium-250

0.001

Californium-251

0.001

Californium-252

0.001

Californium-253

0.1

Californium-254

0.001

Any alpha emitting radionuclide not listed above or mixtures of alpha emitters of unknown composition

0.001

Einsteinium-250

100

Einsteinium-251

100

Einsteinium-253

0.1

Einsteinium-254m

1

Einsteinium-254

0.01

Fermium-252

1

Fermium-253

1

Fermium-254

10

Fermium-255

1

Fermium-257

0.01

Mendelevium-257

10

Mendelevium-258

0.01

Any radionuclide other than alpha emitting radionuclides not listed above, or mixtures of beta emitters of unknown composition

Submit comments by November 24, 2014. Comments received after this date will be considered if it is practical to do so, but the NRC is only able to ensure consideration of comments received on or before this date.

10 CFR Part 20

Summary

The U.S. Nuclear Regulatory Commission (NRC) is issuing this advance notice of proposed rulemaking (ANPR) to obtain input from stakeholders on the development of a draft regulatory basis. The draft regulatory basis would support potential changes to the NRC's current radiation protection regulations. The goal of this effort is to achieve greater alignment between the NRC's radiation protection regulations and the 2007 recommendations of the International Commission on Radiological Protection (ICRP) contained in ICRP Publication 103 (2007). Through this ANPR, the NRC has identified specific questions and issues with respect to a possible revision of the NRC's radiation protection requirements. Stakeholder comments, including responses to the specific questions, will be considered by the NRC staff when it develops the draft regulatory basis. In a separate and related activity, the NRC staff will be preparing an ANPR concerning the NRC's design objectives governing dose assessments for radioactive effluents from light-water-cooled nuclear power reactors, which should be published for public comment during the public comment period for this ANPR. The NRC plans to hold a series of public meetings to promote full understanding of the contemplated action and facilitate public comment.